Rev. 5.00, 09/03, page 411 of 760
13.2 RTC Registers
13.2.1 64-Hz Counter (R64CNT)
The 64-Hz counter (R64CNT) is an 8- bit re ad-only registe r that indicat es th e states of th e RTC
divider circuit, RTC prescaler, and R64CNT between 64 Hz and 1 Hz.
R64CNT is initialized to H'00 by s e tting the RES ET bit in RTC control register 2 (RCR2) or the
ADJ bit in RCR2 to 1.
R64CNT is not initialized by a power-on reset or manual reset, or in standby mode.
Bit 7 is always read as 0.
Bit:76543210
— 1Hz 2Hz 4Hz 8Hz 16Hz 32Hz 64Hz
Initial value:0 ———————
R/W:RRRRRRRR
13.2.2 Second Counter (RSECCNT)
The second counter (RSECCNT) is an 8-bit readable/writable register used for setting/counting in
the BCD-coded second section of the RTC. The count operati on is perfo rmed by a carry for each
second of the 64-Hz counter.
The range that can be set is 00–59 (decimal). Errant operation will result if any other value is set.
Carry out write processing after halting the coun t operation with the START bit i n RCR2.
RSECCNT is not initialized by a power-on reset or manual reset, or in standby mode.
Bit:76543210
— 10 seconds 1 second
Initial value:0 ———————
R/W: R R/W R/W R/W R/W R/W R/W R/W